Despite not using digital effects(to my knowledge), Lars von Trier's "Europa" is absolutely the forerunner for "Sin City" by combining black and white and color, and using back projection instead of a greenscreen combined with the knowing approach to it's genre (Though I think "Europa" is a masterpiece, and "Sin City" is just very good), and it even influenced "Schindler's List". Spielberg apparently even offered von Trier a job in Hollywood!